ClinicalTrials.gg
CompletedNCT05284383Updated Aug 25, 2022

Reducing Nocebo Effects on Pressure Pain

An interventional study of Closed-label nocebo conditioning and Closed-label counterconditioning in Pain and Hyperalgesia, sponsored by Leiden University. Completed at 1 site in Netherlands. Open to female participants aged 18 Years to 35 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2022-08-25.

Sponsored by Leiden University · Not applicable, Interventional, and Basic science

From the registry’s dates

  • Registered 10 months after the study started (first participant enrolled Mar 2021, registered Feb 2022).
Phase
Not applicable
Study type
Interventional
Enrollment
69
Allocation
Randomized
Ages
18 Years to 35 Years
Sex
Female
01

Study summary

Nocebo effects are known to adversely affect the experience of various physical symptoms, such as pain and itch. Nocebo effects can be induced by associative learning mechanisms of classical conditioning. Furthermore, recent studies have shown that counterconditioning can successfully reduce nocebo effects, and to a larger extent than mere extinction, which suggests counterconditioning can be an innovative method for desensitization of symptoms. When using such procedures in clinical practice, deception of patients should be avoided as much as possible. The use of open-label procedures could provide a promising alternative. While previous studies have already shown that open-label placebos are effective, the effects of open-label counterconditioning and closed-label counterconditioning are not extensively investigated in comparison to other strategies, such as extinction, and not yet compared amongst each other. Before implementing such a procedure in clinical practice, it would be relevant to get an insight in the efficacy of both open- and closed-label counterconditioning in healthy participants as compared to extinction and to investigate whether open-label counterconditioning can be equally effective as closed-label counterconditioning. Furthermore, it would be relevant to study the induction and reduction of nocebo effects using a pain modality that mimics the type of pain that people suffering from several chronic pain conditions experience, such as pressure pain. The main aim of the current study is to investigate whether open- and closed-label counterconditioning are more effective in reducing nocebo effects than extinction. To this aim, it will be investigated whether open- and closed-label counterconditioning lead to stronger reductions in nocebo effects on pressure pain than (closed-label) extinction, and whether all three successfully reduce nocebo effects. Finally, it will be tested whether open- and closed label counterconditioning are comparable in effectivity.

Read the detailed description

The primary objective of the study is to investigate whether open- and closed-label counterconditioning are more effective in reducing nocebo effects than extinction.

The experimental (open- and closed-label counterconditioning) and control (extinction) groups will be compared on the change in the nocebo effect from before to after counterconditioning. The nocebo effect is defined as the mean difference in self-reported pain ratings (on a numeric rating scale from 0 (no pain) to 10 (worst pain imaginable))during all experimental trials and control trials in the test phase of nocebo conditioning and the test phase of counterconditioning/extinction. The reduction of the nocebo effect will be determined by calculating the mean difference between the nocebo effect after conditioning and after counterconditioning/extinction. It is expected that participants in both counterconditioning groups will show a larger reduction of the nocebo effect than participants in the extinction group. A one-way ANOVA will be conducted, to examine the main effect of group on the amount of change in nocebo effects. Then, post-hoc analyses will be conducted after the primary analysis, to test for differences between the three forms of nocebo reduction.

Secondary, it will be tested whether all three procedures (open- and closed-label counterconditioning and extinction) lead to a significant reduction of the nocebo effect, by comparing the amount of reduction to test value 0. It is hypothesized that all groups show a significant reduction.

Finally, it will be investigated whether open- and closed-label counterconditioning procedures are comparable in terms of their ability to reduce nocebo effects on pressure pain. Both groups are expected to be comparable in efficacy of reducing the nocebo effect.

02

Conditions studied

  • Pain
  • Hyperalgesia

Keywords

  • Pressure pain
  • Nocebo effect
  • Conditioning
  • Counterconditioning
03

In context

Pain

10,054 studies on the registry are indexed under Pain; 1,649 are open to participants now.

This study's enrollment of 69 is close to the median of 66 across 8,493 interventional studies indexed under Pain.

Browse Pain studies →

Lead sponsor

Leiden University is the lead sponsor of 19 studies on the registry; 3 are open to participants now.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
18 Years to 35 Years
Sexes eligible
Female
Accepts healthy volunteers
Yes

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

  • Aged 18-35 years
  • Good understanding of written and spoken Dutch or English

Exclusion criteria

Exclusion Criteria:

  • Severe somatic or psychiatric morbidity (e.g., heart/lung diseases, psychiatric disorders)
  • Raynaud's disease, chronic pain complaints at present or in the past
  • Current pain complaints (> 2 on NRS)
  • Current use of medication (except for birth-control pill)
  • Injuries on the non-dominant hand
  • Refusal/inability to remove nail polish or artificial nails for the experiment
  • Pregnancy or breastfeeding
Terms in these criteria, in plain language(1)

Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.

DSM diagnostic criteria

The American Psychiatric Association’s manual of mental health diagnoses. DSM-5 (2013, revised as DSM-5-TR in 2022) replaced DSM-IV, and some studies still name the older edition. “Meets DSM criteria for …” means diagnosed by that edition’s diagnostic criteria, usually by a clinician in an interview.

05

Study design

Phase
Not applicable
Primary purpose
Basic science
Allocation
Randomized
Intervention model
Parallel assignment
Masking
None (open label)
Enrollment
69 participants (actual)

Study arms

  • Experimental
    Open-label counterconditioning

    Closed-label conditioning followed by open-label counterconditioning, using moderately painful stimuli (during conditioning) and non-painful stimuli (during counterconditioning), combined with closed-label nocebo suggestions and open-label nocebo reduction suggestions

    Behavioral: Closed-label nocebo conditioning · Behavioral: Open-label counterconditioning

  • Experimental
    Closed-label counterconditioning

    Closed-label conditioning followed by closed-label counterconditioning, using moderately painful stimuli (during conditioning) and non-painful stimuli (during counterconditioning), combined with closed-label nocebo suggestions and closed-label nocebo reduction suggestions

    Behavioral: Closed-label nocebo conditioning · Behavioral: Closed-label counterconditioning

  • Active comparator
    Closed-label extinction

    Closed-label conditioning followed by closed-label extinction, using moderately painful stimuli (during conditioning) and slightly-painful stimuli (during extinction), combined with closed-label nocebo suggestions during conditioning and no/neutral suggestions during extinction

    Behavioral: Closed-label nocebo conditioning · Behavioral: Closed-label extinction

Interventions

  • BehavioralClosed-label nocebo conditioning

    Conditioning consists of a learning and test phase. In the learning phase, a message indicating the sham activation of a Transcutaneous Electrical Nerve Stimulation (TENS) device (CS) will be repeatedly paired with a moderate intensity pressure pain stimulus, whereas a message indicating the deactivation of the sham device will be repeatedly paired with a slightly painful pressure pain stimulus. Participants will be given a verbal suggestion in line with the conditioning procedure (i.e. activation of the device will increase their pain). The testing phase is similar to the learning phase, but a slight pressure pain intensity is used for all trials, to test for a nocebo effect (i.e. to test whether participants score "TENS on" trials as more painful than "TENS off" trials).

  • BehavioralClosed-label counterconditioning

    Counterconditioning consists of a learning and test phase. In the learning phase, a message indicating the sham activation of the TENS device (CS) is now repeatedly paired with a non-painful intensity pressure pain stimulus, whereas a message indicating the sham deactivation of the TENS device will be repeatedly paired with a slightly painful pressure pain stimulus. Participants will be given a verbal suggestion in line with the counterconditioning procedure (i.e. activation of the device will reduce their pain). The testing phase is similar to the learning phase, but a slight pressure pain intensity is used for all trials, to test whether the nocebo effect is successfully reduced (i.e. to test whether participants no longer score "TENS on" trials as more painful than "TENS off" trials or even score "TENS on" trials as less painful).

  • BehavioralOpen-label counterconditioning

    Counterconditioning consists of a learning and test phase. In the learning phase, a message indicating the sham activation of the TENS device (CS) is now repeatedly paired with a non-painful intensity pressure pain stimulus, whereas a message indicating the sham deactivation of the TENS device will be repeatedly paired with a slightly painful pressure pain stimulus. Participants will be given a open-label verbal suggestions in line with the counterconditioning procedure (i.e. they are told counterconditioning will be used to reduce nocebo effects and they are told the device is sham, but that their pain will still be influenced because of the placebo effect). The testing phase is similar to the learning phase, but a slight pressure pain intensity is used for all trials, to test whether the nocebo effect is successfully reduced (i.e. to test whether participants no longer score "TENS on" trials as more painful than "TENS off" trials or even score "TENS on" trials as less painful).

  • BehavioralClosed-label extinction

    Extinction consists of a learning and test phase. In the learning phase, slightly painful stimuli are used for all trials. During the testing phase, again a slight pressure pain intensity is used for all trials, to test whether the nocebo effect is successfully reduced (i.e. to test whether participants no longer score "TENS on" trials as more painful than "TENS off" trials).

06

What researchers measure

Primary outcomes

  1. Nocebo reduction; group comparison

    The change in nocebo effects from after nocebo conditioning (part 1) to after either form of counterconditioning or extinction (part 2) will be compared between groups. The nocebo effect is defined as the difference between the pain scored during experimental trials (on a 0-10 NRS) and during control trials (same NRS). The change is calculated by subtracting the nocebo effect after counterconditioning from the nocebo effect after nocebo conditioning.

    Time frame: On the testing day; testing phase of nocebo induction and reduction

Secondary outcomes

  1. Nocebo reduction

    For all three groups separately, it will be tested whether the nocebo effect is significantly reduced from test phase of nocebo conditioning to the test phase of either form of counterconditioning or extinction. The nocebo effect is defined as the difference between the pain scored during experimental trials (on a 0-10 NRS) and during control trials (same NRS). Nocebo reduction is calculated by subtracting the nocebo effect after counterconditioning from the nocebo effect after nocebo conditioning. For all groups separately, the amount of reduction will be compared to test value 0.

    Time frame: On the testing day; testing phase of nocebo induction and reduction

  2. Nocebo reduction; equivalence of the two forms of counterconditioning

    It will be tested whether the change in nocebo effects from the test phase of conditioning to the test phase of counterconditioning in the open- and closed-label groups is comparable. The nocebo effect is defined as the difference between the pain scored during experimental trials (on 0-10 NRS) and during control trials (same NRS). The change is calculated by subtracting the nocebo effects after counterconditioning from the nocebo effect after nocebo conditioning.

    Time frame: On the testing day; testing phase of nocebo induction and reduction

07

Study locations

1 site
  • Leiden University
    Leiden, 2333AK, Netherlands
08

References and documents

Individual participant data

Plan to share: Yes — All data are collected pseudonymised; consent forms are the only sources containing personal data and will not be shared, but are monitored by the department's Data Monitor.

Supporting information: Statistical analysis plan, Analytic code

Time frame: Data will become available immediately after study publication and will be retained for 15 years.

Access criteria: Data can be shared with scientists in relevant fields for the purpose of future studies such as replication or meta-analysis (or with designated persons for monitoring purposes).

No publications or documents are linked to this record.

09

Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Aug 25, 2022, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
10

Registry details

Key details

Study ID
NCT05284383
Lead sponsor
Leiden University
Responsible party
Andrea W.M Evers, PhD (Professor, Leiden University Medical Center) — Principal investigator
First posted
Mar 17, 2022
Start date
Mar 23, 2021
Primary completion
Apr 5, 2022
Completion
Apr 5, 2022
Last update
Aug 25, 2022

Study contacts

Andrea Evers, Prof
principal investigator · Leiden University

Oversight

Data monitoring committee
Yes
FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

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